Improvement in switches for electric lights



W. ELSAWYER & A. MAN. Switch for Electric-Light.

No. 210,152. Pagented Nov. 19,1878.

UNITED STATES PATENT FFIGE.

WILLIAM E. SrUVYER, OF NE\V YORK, AND ALBON MAN, OF BROOKLYN, N. Y.

lMPROVEMENT IN SWITCHES FOR ELECTREO LlGHTS.

Specification forming part of Letters Patent X0. 210,152, dated November 19, lSTe'; application filed O tober 15, 1878.

To all about it may concern:

Be it known that we, WILLIAM EDWARD Snwvnn, or the city, county, and State of New York, and ALBON MAN, of the city of Brooklyn, in the county of Kings and State aforesaid, have jointly invented certain new and useful Improvements in Electrical Lightin rrpparatus and Circuits; and we do here by declare the following to be a description of the same, and of the manner and process of making, constructing, and using them, in such full, clear, concise, and exact terms as to on able any person skilled in the art or science to which it appertains, or with which it is most nearly connected, to make, construct, and use the same, reference being had to the acconr panying drawings, making partof this specification, and to certain Letters Patent of the United States heretofore granted to us for certain inventioi'ls hereunto appertaining, and to whic especial reference will hereinafter be made.

In Letters Patent of the United States No. 205,303 we have shown and described an electric-lamp-iighting switch, which not onlyturns the current on to and off from the lamp gradually, but admits of regulating the light proceeding from the lamp to any desired inteir sity; and in the same Letters Patent we have described a distributing system, by means of which. the current from a single generator may be divided among any number of lamps.

Our present invention comprises anewlam plighting switch, which not only accomplishes the purpose of the switch above referred to, but is provided also with a safety device, the nature of which will be explained in detail hereinafter.

In the drawing accompanying and forming a part of this specification, Figure 1 illustrates our electric-lamp-lighting switch.

iefercnee being had to Fig. 1, it consists of a suitable metallic holder, A, grooved so as to keep a sliding piece, B, in place. To the sliding piece B is fixed a flat spring, I), carrying at one end a cross-piece, b, which, as the slide is moved, makes contact with the sixteen pins, E E and E E, arranged eight on each side of the spring.

The movement of the slide B backward and forward is accomplished by turning the crank D and l), which works upon the stud d. At each revolution of the crank the pin 0, iixed in the hub of the crank, engages with a tooth, O, and moves the slide forward one tooth, until it has acted upon the last tooth, when farther movement is prevented by the contact of the cross piece 1/ with the stop-pin 1). Turning the crank in the opposite direction in like manner moves the slide backward until its movement is arrested by the contact of the pin a with the armature-lever G.

In lighting a lamp such as that shown and described in Letters Patent No. 205,144, grant ed to us as aforesaid, we have found it im portant to turn on the current gradually, otherwise fractures of the carbon may ensue. It is possible that at times, when the current is fully turned on the lamp, there may occur an interruption in the supply; extinguislnnent of the light follows, and the carbon grows cool. Suppose, now, that the circuit of the lamp not having been destroyed, but being set for the full force of the current, the supply is suddenly renewed; instantly the carbon is heated from a low to an extremely high temperature, and its fracture may be expected. The electromagnet F attached to the switch effectually guards against this danger. Unless the current is circulating in its coils the lamp cannot be lighted, and if there is an interruption in the supply the current cannot circulate in its coils, although the supply may be renewed, until the lamp shall first have been taken out of the circuit.

The armature F is fixed to the bent lever G, pivoted at 0, one extremity of which plays between the studs g and g, according as the magnet is or is not actuated by the current. The spring f acts to force the armature away from the magnet, and establish aconnection. between the lever Gr and stud g.

The current from the side of the generator enters the lever G, and, wheirthe circuit is in. its normal condition, passes by way of the stud g through the coils of magnet F to the holder A; then, by way of slide l3, spring I), cross-piece b, and the eight pins E, to the lamp, and outward at the point. A sudden interruption occurs. instantly the armature is forced away from the magnet by the spring f, and contact of the lever G with the stud g is established.

The lamp is now entirely out of the circuit, and the current flows solely from the lever through stud g and resistance R'outward at thepoint. It is in this position we have shown the switch; nor can the lamp ever be relighted unless the slide B be moved back until the cross-piece 1) makes connection with 1 E, when the pin a strikes the lever G and forces the armature within the grasp of the magnet, at the same time establishing a connection between G and g. Then, if there be a supply of current, the lamp may be lighted by moving the slide B forward; but if there be no supply, moving the slide forward will simply release the armature, and the lever G will again move to the stud g. By this device even carelessness is rendered harmless, and, inasmuch as seven turns of the crank are required to fully light the lamp, the current is not likely ever to be turned on very rapidly.

We have found that the internal resistance of a lamp such as that of Letters Patent No.

205,144 is not far from six-tenths of an ohm.

It is clearly important, to the end that other lamps in the circuit may not be affected, that the resistance of the circuit from the to the points shall be constant, whether the lamp be in or out of the circuit, or whether it be lighted feebly or at its full head. Therefore, when the lamp is out of the circuit-t. 0., the cross-piece b resting upon the pins 1 1-the current flows by way of pin 1 E through the .6 ohm resistance R and outward at the point. Thus when the lamp is entirely out out the resistance of the circuit is precisely the same as when the lamp is fully lighted. The pins 1 E and 8 E serve no useful purpose other than tokeep the cross-piece I) in position.

Assuming, now, that it is desired to light the lamp, the current is let on by sevenths; but any other small fraction may be substituted. A single turn of the crank advances the crosspiece 1) upon the two pins 2 2. The current divides, six-sevenths of it passing through resistance R, of .1 ohm, and resistance R, of .6 ohm, outward at the-point, the other seventh passing through the several resistance- R amounting altogether to 3.6 ohms, and through the lamp of .6 ohm outward at the point. The resistance of the first circuit,

which we will call the shunt, is therefore .7 l

ohm, and that of the lamp is 4.2 ohms, makin g the resistance from the point to thepoints .6 ohm.

At the next turn of the crank the crosspiece I) bears upon pins 3 3, and the resistance is as follows: In the shunt-circuit .84

ohm, in the lamp-circuit 2.1:.6 ohm.

Upon pins 4 4 the resistance is in the shuntcuit or in other circuits are absolutely uuaffected.

I In the Letters Patent granted to us hereinbefore referred to we have fully set forth and claimed these important features; but we consider the switch above described an improvement upon the methods set forth in said Let ters Patent, though we do not intend to limit our patent of which this is the specification to any particular form of apparatus or special application of the invention, but intend to claim all forms and applications of the invention that fall within the substance of its scope.

For distributing the current from a single generator to two or more electric lamps, engines, or other apparatus, we have recourse to a commutator in connection with the generator, which, when these are two circuits from the generator, transmits the electric impulses alternately into each, and, when there are more than two circuits, transmits these impulses sem'ctim into the several circuits.

This commutator and system of distribution we intend to make the subj cot-matter of a separate patent.

Having thus fully described our invention, we claim and desire to secure by Letters Patent i 1. The combination, with an electric-lamplighting switch, of an apparatus which operates to prevent the completion of the lamp' circuit when there is no current to energize the lamp. V

2. The combination, with an electric-lamplighting switch, of an apparatus energized by the current which actuates the lamp, and that operates when there is an interruption in the flow of the current to close the circuit of the hamp against a sudden recurrence of such 3. The combination, with an electric lamp and a lamp-lighting switch, of two electrical circuits connected therewith, the switch operating to reduce the resistance of one circuit and increase the resistance of the other in such manner that at each reduction in the resistance of one circuit there will be an increase in the resistance of the other.

4. The combination of an electric lamp and a lamp-lighting switch of electrical circuits, so arranged that as the resistance in the circuit of the lamp is lessened, and consequently more current caused to flow through the lamp,

the resistance of an extraneous channel or channels is increased, each reduction in the resistance of the lamp-circuit being accompa nied by such increase in the resistance of the extraneous channel or channels that the resistance of the main or branch circuit, which contains the circuit of the lamp and the extraneous channel or channels is maintained constant, or nearly so.

5. An electric lanip-lighting switch or apparatus which, after an interruption in the flow of current, operates to prevent the lighting of the lamp until it shall have first been brought into the position which it occupies when the lamp is not lighted.

WILLIAM EDlVARD SAXVYER. ALBON MAN. Witnesses:

Amos BROADNAX, THOMAS SAULT. 

